Unfortunately the link in the exception text, http://go.microsoft.com/fwlink/?LinkId=70353, is broken. However, it used to lead to http://msdn.microsoft.com/en-us/library/ms733768.aspx which explains how to set the permissions.
It basically informs you to use the following command:
netsh http add urlacl url=http://+:80/MyUri user=DOMAIN\user
You can get more help on the details using the help of netsh
For example: netsh http add ?
Gives help on the http add
command.